During a breakfast roundtable at Mix With The Masters this spring, we discussed how you can power a small clock by using a potato. So, why couldn't you use a potato to drive a speaker cabinet? We had to try it!!! With the help of the workshop attendees, I cut a standard speaker wire in half and inserted a pair of potatoes in line. One potato for the positive side and one potato for the negative side. Just jabbed the wires into them. Then we connected our potato-modified speaker cable between a Marshall head and a 4x12 cabinet and tried to play a guitar through it. Unfortunately the Marshall tube amp kept blowing fuses even though our ohmage measurements showed that it would work. But we did not give up. It was not until we tried the solid state amplifier that our experiment worked. Here is a video of our potato filter triumph.

What does it sound like? To answer that, Mike Fradis from Waves and I spent a day re-creating the potato filter and trying other items inserted into the speaker cable, taking detailed measurements and documenting the effect to the audio signal.

In general, these were our findings:

Potatoes: attenuation and a slight high frequency shelving.
Apples, bananas, carrots, oranges: Different levels of attenuation, depending on the size of the item with light high pass filtering.
Hot dog: Very flat response with attenuation. Slicing the hot dogs in half will reduce the amount of attenuation. We were very impressed with the hot dogs.

Interesting, you say? Well that was only the beginning. Mike Fradis and I also set up a series of experiments running the speaker lines through various power tools and kitchen appliances. This was something Ed Cherney suggested I try. Basically the idea is to cut the cord off a powered drill and connect the speaker cable to run audio through the drill. Amazingly when you hit the right notes, the drill will start up, being powered entirely by the audio. And what a crazy sound that is! I've used this technique while recording guitar solos. The sound of the guitar is full of whirring and grinding sounds as the motors are running. You can try it with blenders, hair dryers, jigsaws, vacuum cleaners. Different motors have different characters. I've now built a jig so it is simple and non destructive to change out different motors.